Hamble River fort and chain tower

Description

Documentary source refers to a the presence of a small wooden fort, built at Oyster Hard, in the C15. It was one end of a chain 'boom defense' which stretched across the river. In 1922 part of the large iron chain was found (no source given). (Hampshire AHBR)

Soper had already fortified Hamble against the French with a wooden tower and a spiked pale running along the sea-shore and he had built two naval storehouse there. The long stretch of the Hamble River made a very suitable and comparatively safe resting-place and as a further precaution a great iron chain was placed across the estuary. Within the area protected by the chain Soper proceeded to lay up the four greatest shops which were brought in one by one over a period of years. (Carpenter-Turner)

When Catton retired in 1420 rewarded for his labours by the grant of the Gabriel de la Tour, and the Grand Gabriel, a definite attempt seems to have been made to consolidate and reorganise the administration of the king's ships. Soper was appointed clerk, and, while the building of the Gracedieu continued at Southampton, facilities were also to be provided for the repair and refitting of the other ships in the same port. His salary was more than doubled from a shilling a day to forty pounds a year, with provision for a deputy. (Preamble to Soper's accounts: E364/61. His salary was paid fairly regularly until 1436) The main anchorage of the king's great ships in the Hamble river was also to be fortified, to guard against the possibility of French raids, a familiar hazard in Southampton Water but unlikely in the waters of the Pool of London or off Greenwich or Deptford. (Rose 1982)

In 1418 the "Grace Dieu," the largest ship ever built in England at that time, was brought to Hamble for fitting out. Her Southampton builder, William Soper, had two storehouses in Hamble and had erected a wooden tower at the river entrance for protection against French raids. During the 15th century many 'Royal' ships used the river and a number of them were laid up here. The wreck of the "Grace Dieu" lies in the river mud to this day. (Ian Underdown 1999)

Comments

The Hamble was a place where medieval warships were fitted out and some protection of these naval works may well be expected but seemingly the primary source is a reference for an intent to make a fortification. None of the usual coastal defenses historians mention this C15 fort and the recorded defences of the Hamble are references to the C16 St Andrews Fort. The place-name Oyster Hard does not occur on OS maps but is one of several 'hards' being bands of rock in the otherwise soft intertidal muds of the river. If there was a chain across the river then one of these would have been likely to be the base of if (although Ferry Hard, is nearer the mouth and would have a short span); however the layout of mouth of the Hamble has undergone changes. St Andrews could not possibly have been the site for a harbour chain or boom and the shorter effective range of C15 artillery, compared to C16 artillery, might also suggest a location roughly as given if there was a C15 fort. St Andrews might also be a new build reflecting not just an increased artillery range but changes to the course of the Hamble which made the older site redundant.
What terms were actually used in the primary source? Gatehouse has not seen the original source, which is not included in Rose's transcriptions. These do mention wooden stakes and pile providing security fot the kings ship but Gatehouse considers these to be reference to wharfs and jetties and not to a stacked fence on the shore as seemingly suggested by Carpenter-Turner. A timber tower is unlikely to have held artillery but could have been a watch tower. A ground level earthwork with supplementary wooden buildings (Is the term used ligna fortalicia? ) is, on the other hand, quite possible and this ship builder did have had access to cannon and powder (although the cannon mentioned in Rose's transcriptions are all specifically for named ships). The evidence for a chain across the river mouth seems particularly weak, since the piece of chain found could have come from other sources (lost anchor chain?) and from quite a long period.
Information on the primary historical source for this C15 tower would be most welcome.